@article{60453, abstract = {{ The most popular and actively researched class of quad remeshing techniques is the family of parametrization based quad meshing methods . They all strive to generate an integer-grid map , i.e. a parametrization of the input surface into R 2 such that the canonical grid of integer iso-lines forms a quad mesh when mapped back onto the surface in R 3 . An essential, albeit broadly neglected aspect of these methods is the quad extraction step, i.e. the materialization of an actual quad mesh from the mere "quad texture". Quad (mesh) extraction is often believed to be a trivial matter but quite the opposite is true: numerous special cases, ambiguities induced by numerical inaccuracies and limited solver precision, as well as imperfections in the maps produced by most methods (unless costly countermeasures are taken) pose significant challenges to the quad extractor. We present a method to sanitize a provided parametrization such that it becomes numerically consistent even in a limited precision floating point representation. Based on this we are able to provide a comprehensive and sound description of how to perform quad extraction robustly and without the need for any complex tolerance thresholds or disambiguation rules. On top of that we develop a novel strategy to cope with common local fold-overs in the parametrization. This allows our method, dubbed QEx , to generate all-quadrilateral meshes where otherwise holes, non-quad polygons or no output at all would have been produced. We thus enable the practical use of an entire class of maps that was previously considered defective. Since state of the art quad meshing methods spend a significant share of their run time solely to prevent local fold-overs, using our method it is now possible to obtain quad meshes significantly quicker than before. We also provide libQEx, an open source C++ reference implementation of our method and thus significantly lower the bar to enter the field of quad meshing. }}, author = {{Ebke, Hans-Christian and Bommes, David and Campen, Marcel and Kobbelt, Leif}}, issn = {{0730-0301}}, journal = {{ACM Transactions on Graphics}}, number = {{6}}, pages = {{1--10}}, publisher = {{Association for Computing Machinery (ACM)}}, title = {{{QEx}}}, doi = {{10.1145/2508363.2508372}}, volume = {{32}}, year = {{2013}}, } @article{60452, abstract = {{Quadrilateral remeshing approaches based on global parametrization enable many desirable mesh properties. Two of the most important ones are (1) high regularity due to explicit control over irregular vertices and (2) smooth distribution of distortion achieved by convex variational formulations. Apart from these strengths, state-of-the-art techniques suffer from limited reliability on real-world input data, i.e. the determined map might have degeneracies like (local) non-injectivities and consequently often cannot be used directly to generate a quadrilateral mesh. In this paper we propose a novel convex Mixed-Integer Quadratic Programming (MIQP) formulation which ensures by construction that the resulting map is within the class of so called Integer-Grid Maps that are guaranteed to imply a quad mesh. In order to overcome the NP-hardness of MIQP and to be able to remesh typical input geometries in acceptable time we propose two additional problem specific optimizations: a complexity reduction algorithm and singularity separating conditions. While the former decouples the dimension of the MIQP search space from the input complexity of the triangle mesh and thus is able to dramatically speed up the computation without inducing inaccuracies, the latter improves the continuous relaxation, which is crucial for the success of modern MIQP optimizers. Our experiments show that the reliability of the resulting algorithm does not only annihilate the main drawback of parametrization based quad-remeshing but moreover enables the global search for high-quality coarse quad layouts - a difficult task solely tackled by greedy methodologies before.}}, author = {{Bommes, David and Campen, Marcel and Ebke, Hans-Christian and Alliez, Pierre and Kobbelt, Leif}}, issn = {{0730-0301}}, journal = {{ACM Transactions on Graphics}}, number = {{4}}, pages = {{1--12}}, publisher = {{Association for Computing Machinery (ACM)}}, title = {{{Integer-grid maps for reliable quad meshing}}}, doi = {{10.1145/2461912.2462014}}, volume = {{32}}, year = {{2013}}, } @article{60451, abstract = {{Nowadays, digital 3D models are in widespread and ubiquitous use, and each specific application dealing with 3D geometry has its own quality requirements that restrict the class of acceptable and supported models. This article analyzes typical defects that make a 3D model unsuitable for key application contexts, and surveys existing algorithms that process, repair, and improve its structure, geometry, and topology to make it appropriate to case-by-case requirements. The analysis is focused on polygon meshes, which constitute by far the most common 3D object representation. In particular, this article provides a structured overview of mesh repairing techniques from the point of view of the application context. Different types of mesh defects are classified according to the upstream application that produced the mesh, whereas mesh quality requirements are grouped by representative sets of downstream applications where the mesh is to be used. The numerous mesh repair methods that have been proposed during the last two decades are analyzed and classified in terms of their capabilities, properties, and guarantees. Based on these classifications, guidelines can be derived to support the identification of repairing algorithms best-suited to bridge the compatibility gap between the quality provided by the upstream process and the quality required by the downstream applications in a given geometry processing scenario.}}, author = {{Attene, Marco and Campen, Marcel and Kobbelt, Leif}}, issn = {{0360-0300}}, journal = {{ACM Computing Surveys}}, number = {{2}}, pages = {{1--33}}, publisher = {{Association for Computing Machinery (ACM)}}, title = {{{Polygon mesh repairing}}}, doi = {{10.1145/2431211.2431214}}, volume = {{45}}, year = {{2013}}, } @article{60450, abstract = {{AbstractThe computation of intrinsic, geodesic distances and geodesic paths on surfaces is a fundamental low‐level building block in countless Computer Graphics and Geometry Processing applications. This demand led to the development of numerous algorithms – some for the exact, others for the approximative computation, some focussing on speed, others providing strict guarantees. Most of these methods are designed for computing distances according to the standard Riemannian metric induced by the surface's embedding in Euclidean space. Generalization to other, especially anisotropic, metrics – which more recently gained interest in several application areas – is not rarely hampered by fundamental problems. We explore and discuss possibilities for the generalization and extension of well‐known methods to the anisotropic case, evaluate their relative performance in terms of accuracy and speed, and propose a novel algorithm, the Short‐Term Vector Dijkstra. This algorithm is strikingly simple to implement and proves to provide practical accuracy at a higher speed than generalized previous methods.}}, author = {{Campen, Marcel and Heistermann, Martin and Kobbelt, Leif}}, issn = {{0167-7055}}, journal = {{Computer Graphics Forum}}, number = {{5}}, pages = {{63--71}}, publisher = {{Wiley}}, title = {{{Practical Anisotropic Geodesy}}}, doi = {{10.1111/cgf.12173}}, volume = {{32}}, year = {{2013}}, } @inproceedings{60454, author = {{Zimmer, Henrik and Campen, Marcel and Kobbelt, Leif}}, booktitle = {{2013 IEEE Conference on Computer Vision and Pattern Recognition}}, publisher = {{IEEE}}, title = {{{Efficient Computation of Shortest Path-Concavity for 3D Meshes}}}, doi = {{10.1109/cvpr.2013.280}}, year = {{2013}}, } @article{58526, author = {{Masri, Leila and Schulte, Rebecca D. and Timmermeyer, Nadine and Thanisch, Stefanie and Crummenerl, Lena Luise and Jansen, Gunther and Michiels, Nico K. and Schulenburg, Hinrich}}, journal = {{Ecology Letters}}, keywords = {{Bacillus thuringiensis, Bateman’s principle, Caenorhabditis elegans, ecological immunology, host–parasite coevolu- tion, Red Queen hypothesis, sexual selection}}, number = {{16}}, pages = {{461--468}}, title = {{{Sex differences in host defence interfere with parasite- mediated selection for outcrossing during host–parasite coevolution}}}, doi = {{10.1111/ele.12068}}, year = {{2013}}, } @article{38006, author = {{Schoch, Roland and Desens, Willi and Werner, Thomas and Bauer, Matthias}}, issn = {{0947-6539}}, journal = {{Chemistry - A European Journal}}, keywords = {{T3, CSSD}}, number = {{47}}, pages = {{15816--15821}}, publisher = {{Wiley}}, title = {{{X-ray Spectroscopic Verification of the Active Species in Iron-Catalyzed Cross-Coupling Reactions}}}, doi = {{10.1002/chem.201303340}}, volume = {{19}}, year = {{2013}}, } @inbook{56039, author = {{Priesching, Nicole}}, booktitle = {{Welt-geistliche Frauen in der Frühen Neuzeit. Studien zum weiblichen Semireligiosentum}}, editor = {{Conrad, Anne}}, pages = {{141–163}}, title = {{{Gehören Beginen zum „Semireligiosentum“? Laienfrömmigkeit und Ordensideale}}}, volume = {{73}}, year = {{2013}}, } @article{13517, author = {{Jesser, Anton and Rohrmüller, Martin and Schmidt, Wolf Gero and Herres-Pawlis, Sonja}}, issn = {{0192-8651}}, journal = {{Journal of Computational Chemistry}}, number = {{1-2}}, pages = {{1--17}}, title = {{{Geometrical and optical benchmarking of copper guanidine-quinoline complexes: Insights from TD-DFT and many-body perturbation theory†}}}, doi = {{10.1002/jcc.23449}}, volume = {{35}}, year = {{2013}}, } @article{13521, author = {{Sanna, S. and Rode, S. and Hölscher, R. and Klassen, S. and Marutschke, C. and Kobayashi, K. and Yamada, H. and Schmidt, Wolf Gero and Kühnle, A.}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, title = {{{Charge compensation by long-period reconstruction in strongly polar lithium niobate surfaces}}}, doi = {{10.1103/physrevb.88.115422}}, volume = {{88}}, year = {{2013}}, } @article{13523, author = {{Longo, Roberto C. and Cho, Kyeongjae and Schmidt, Wolf Gero and Chabal, Yves J. and Thissen, Peter}}, issn = {{1616-301X}}, journal = {{Advanced Functional Materials}}, pages = {{3471--3477}}, title = {{{Monolayer Doping via Phosphonic Acid Grafting on Silicon: Microscopic Insight from Infrared Spectroscopy and Density Functional Theory Calculations}}}, doi = {{10.1002/adfm.201202808}}, volume = {{23}}, year = {{2013}}, } @article{13522, author = {{Aldahhak, Hazem and Schmidt, Wolf Gero and Rauls, E.}}, issn = {{0039-6028}}, journal = {{Surface Science}}, pages = {{242--248}}, title = {{{Adsorption of PTCDA on NaCl(100) and KCl(100)}}}, doi = {{10.1016/j.susc.2013.08.003}}, volume = {{617}}, year = {{2013}}, } @article{13518, author = {{Frigge, T. and Wall, S. and Krenzer, B. and Wippermann, St. and Sanna, S. and Klasing, F. and Hanisch-Blicharski, A. and Kammler, M. and Schmidt, Wolf Gero and Horn-von Hoegen, M.}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, pages = {{149602}}, title = {{{Friggeet al.Reply:}}}, doi = {{10.1103/physrevlett.111.149602}}, volume = {{111}}, year = {{2013}}, } @article{13519, author = {{Riefer, A. and Sanna, S. and Schmidt, Wolf Gero}}, issn = {{0015-0193}}, journal = {{Ferroelectrics}}, pages = {{78--85}}, title = {{{LiNb1-xTaxO3Electronic Structure and Optical Response fromFirst-PrinciplesCalculations}}}, doi = {{10.1080/00150193.2013.821904}}, volume = {{447}}, year = {{2013}}, } @article{13528, author = {{George, B. M. and Behrends, J. and Schnegg, A. and Schulze, T. F. and Fehr, M. and Korte, L. and Rech, B. and Lips, K. and Rohrmüller, M. and Rauls, E. and Schmidt, Wolf Gero and Gerstmann, Uwe}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, number = {{13}}, title = {{{Atomic Structure of Interface States in Silicon Heterojunction Solar Cells}}}, doi = {{10.1103/physrevlett.110.136803}}, volume = {{110}}, year = {{2013}}, } @article{13527, author = {{Rohrmüller, M. and Herres-Pawlis, S. and Witte, M. and Schmidt, Wolf Gero}}, issn = {{0192-8651}}, journal = {{Journal of Computational Chemistry}}, pages = {{1035--1045}}, title = {{{Bis-μ-oxo and μ-η2:η2-peroxo dicopper complexes studied within (time-dependent) density-functional and many-body perturbation theory}}}, doi = {{10.1002/jcc.23230}}, volume = {{34}}, year = {{2013}}, } @article{13525, abstract = {{The frequency-dependent dielectric function and the second-order polarizability tensor of ferroelectric LiNbO3 are calculated from first principles. The calculations are based on the electronic structure obtained from density-functional theory. The subsequent application of the GW approximation to account for quasiparticle effects and the solution of the Bethe-Salpeter equation for the stoichiometric material yield a dielectric function that slightly overestimates the absorption onset and the oscillator strength in comparison with experimental measurements. Calculations at the level of the independent-particle approximation indicate that these deficiencies are, at least, partially related to the neglect of intrinsic defects typical for the congruent material. The second-order polarizability calculated within the independent-particle approximation predicts strong nonlinear coefficients for photon energies above 1.5 eV. The comparison with measured data suggests that the inclusion of self-energy effects in the nonlinear optical response leads to a better agreement with experiments. The intrinsic defects of congruent samples reduce the optical nonlinearities, in particular, for the 21 and 31 tensor components, further improving the agreement between experiments and theory.}}, author = {{Riefer, Arthur and Sanna, Simone and Schindlmayr, Arno and Schmidt, Wolf Gero}}, issn = {{1550-235X}}, journal = {{Physical Review B}}, number = {{19}}, publisher = {{American Physical Society}}, title = {{{Optical response of stoichiometric and congruent lithium niobate from first-principles calculations}}}, doi = {{10.1103/PhysRevB.87.195208}}, volume = {{87}}, year = {{2013}}, } @article{13526, author = {{Eberhard, Jens and Stoll, Ion and Brockhinke, Regina and Neumann, Beate and Stammler, Hans-Georg and Riefer, Arthur and Rauls, Eva and Schmidt, Wolf Gero and Mattay, Jochen}}, issn = {{1466-8033}}, journal = {{CrystEngComm}}, number = {{21}}, title = {{{Structural variety of 5-fluoroarene-2-aminopyrimidine in comparison to 2-aminopyrimidine silver(i) coordination polymers: progress report and overview}}}, doi = {{10.1039/c2ce26388b}}, volume = {{15}}, year = {{2013}}, } @article{15867, author = {{Tautz, Raphael and Da Como, Enrico and Wiebeler, Christian and Soavi, Giancarlo and Dumsch, Ines and Fröhlich, Nils and Grancini, Giulia and Allard, Sybille and Scherf, Ullrich and Cerullo, Giulio and Schumacher, Stefan and Feldmann, Jochen}}, issn = {{0002-7863}}, journal = {{Journal of the American Chemical Society}}, pages = {{4282--4290}}, title = {{{Charge Photogeneration in Donor–Acceptor Conjugated Materials: Influence of Excess Excitation Energy and Chain Length}}}, doi = {{10.1021/ja309252a}}, year = {{2013}}, } @article{15866, author = {{Ardizzone, Vincenzo and Lewandowski, Przemyslaw and Luk, M. H. and Tse, Y. C. and Kwong, N. H. and Lücke, Andreas and Abbarchi, Marco and Baudin, Emmanuel and Galopin, Elisabeth and Bloch, Jacqueline and Lemaitre, Aristide and Leung, P. T. and Roussignol, Philippe and Binder, Rolf and Tignon, Jerome and Schumacher, Stefan}}, issn = {{2045-2322}}, journal = {{Scientific Reports}}, title = {{{Formation and control of Turing patterns in a coherent quantum fluid}}}, doi = {{10.1038/srep03016}}, year = {{2013}}, }